#28 explicit command export -no glob pattern

[Brett Schwarz]

In itcl_cmds.c, all of the itcl commands are exported
using the itcl::* glob pattern. With the recent
addition of the itcl::is command, there was concern
that itcl::is imported ("is") was not a good idea. So,
itcl::is will not be able to be exported. Hence, each
of the itcl commands that are exportable, need to be
explicitly exported in itcl_cmds.c (i.e. itcl::body,
itcl::class, etc).

[Brett Schwarz]

explicit command export patch